| Pin | Name | Description | 
  
    | 1 | Ground |  | 
  
    | 2 | Ground |  | 
  
    | 3 | Ground |  | 
  
    | 4 | Ground |  | 
  
    | 5 | -12V | -12 VDC | 
  
    | 6 | +5V | +5 VDC | 
  
    | 7 | +12V | +12 VDC | 
  
    | 8 | +12V | +12 VDC | 
  
    | 9 | ? | ? | 
  
    | 10 | PWM | Regulates speed of the drive | 
  
    | 11 | PH0 | Control line to send commands to the drive | 
  
    | 12 | PH1 | Control line to send commands to the drive | 
  
    | 13 | PH2 | Control line to send commands to the drive | 
  
    | 14 | PH3 | Control line to send commands to the drive | 
  
    | 15 | WrReq- | Turns on the ability to write data to the drive | 
  
    | 16 | HdSel | Control line to send commands to the drive | 
  
    | 17 | Enbl2- | Enables the Rd line (else Rd is tri-stated) | 
  
    | 18 | Rd | Data actually read from the drive | 
  
    | 19 | Wr | Data actually written to the drive |